铁氰化钆修饰电极对鸟嘌呤的电催化氧化及应用  

Electrocatalytic Oxidation of Guanine at Gadolinium Hexacyanoferrate Modified Electrode and its Application

作　　者：陆云[1] 艾仕云[1] 姜林[1] 李金焕[1] 马娟[1] 

机构地区：[1]山东农业大学化学与材料科学学院,泰安271018

出　　处：《分析化学》2008年第9期1277-1280,共4页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金(No.Y2006B20);山东省自然科学基金(No.Y2006B20)资助项目

摘　　要：用电化学沉积法制备了稀土铁氰化钆修饰玻碳电极(GdHCF/GC/CME),考察了该电极对鸟嘌呤的电催化氧化性能,同时根据Fenton反应产生的羟基自由基对鸟嘌呤的氧化作用和修饰电极氧化作用之间的竞争机理,对抗坏血酸清除羟基自由基进行了初步评价。实验结果表明,修饰电极对鸟嘌呤具有很好的电催化氧化性能。在HAc-NaAc缓冲液(pH=5.1)中,鸟嘌呤在1.0×10-6～4.6×10-5mol/L浓度范围内与其氧化峰电流呈良好的线性关系,其线性回归方程为Ip(μA)=0.1112C+2.8715,r=0.9889;检出限为3.3×10-7mol/L。以此电极评价抗坏血酸对羟基自由基的清除作用,取得了较好的效果,为羟基自由基清除剂的筛选提供了一种新的方法。The gadolinium hexacyanoferrate film modified glassy carbon electrode （ GdHCF/GC/CME ） was prepared by electrochemical deposition, and the electrocatalytic oxidation of guanine at GdHCF/GC/CME was investigated. Based on competitive mechanism between oxidation of guanine by hydroxyl radicals from Fenton reaction and oxidation of guanine at modified electrode, scavenging action of ascorbic acid to free hydroxyl radicals had been primarily evaluated. The results show that electrocataytic activities for oxidation of guanine at GdHCF/GC/CME is very good. The guanine was measured in HAc-NaAc buffer solution （pH = 5.1 ） , its oxidation peak current of guanine vs its concentration has good linear relation in the range of 1.0 ×10^-6 _ 4.6 ×10^-5 mol/L at GdHCF/GC/CME. The regression equation is ip （μA） = 0.1112C ＋ 2.8715, r = 0. 9889 and the detection limit is 3.3×10^-7mol/L. Meanwhile it can be suitable to evaluate the scavenging action of ascorbic acid to free hydroxyl radicals. This work provide a new method for screening of free hydroxyl radicals scavenger as well.

关 键 词：化学修饰电极 铁氰化钆 鸟嘌呤 羟基自由基 抗坏血酸 

分 类 号：O646[理学—物理化学]